Low friction fluid bearing and turbine using same

ABSTRACT

A low friction bearing comprises a first element having a first surface. A second element having a second surface is rotatable about a centerline relative to the first element. A flow passage extends radially outward between the first surface and the second surface. The first surface and the second surface are separated by a fluid flow. The two surfaces are complementary and positioned in close proximity. The bearing finds a preferred application in a fluid cooled turbine to create a high temperature, high efficiency turbine.

TECHNICAL FIELD

The present invention relates generally to low friction fluid bearings,and more particularly to turbines using low friction fluid bearings.

BACKGROUND ART

A variety of rotational devices are dependent upon load supportingbearings for operation. Because traditional bearings include componentssuch as ball bearings, that are almost constantly in motion duringdevice operation, heat caused by friction can build very quickly withinthe bearing. In addition, the bearing surfaces wear over time, which canfurther increase heat generation and friction losses. Eventually, almostall bearings fail due to excessive wear and the detrimental effects ofheat on the components and lubricants. Because it is desirable tooperate most rotational devices at or near their highest rpm level inorder to optimize the amount of work produced, it should be appreciatedthat a bearing exposed to reduced amounts of friction would allow thesedevices to operate closer to their optimum levels while reducing thelikelihood of bearing failure.

In one specific example, turbine engines necessarily include rotatingelements that are interconnected to stationary elements via bearings.Because the turbine and bearings are often subjected to relatively highrotation rates and high temperatures, various components must often beconstructed from exotic materials, such as ceramics and/or expensivetemperature resistant metallic alloys. Because engine efficiencygenerally increases with both speed and temperature, engineers areconstantly seeking ways to operate turbines even faster and at highertemperatures. However, the limitations of available materials placeconstraints in this area. One response to these constraints have beenefforts to introduce cooling circuits into a turbine so that it can beoperated at higher temperatures and/or utilize less exotic metallicalloys. However, in order to introduce a cooling fluid circuit into theturbine, there must necessarily be fluid seals that often have a greatdeal of difficulty withstanding the relatively hot hostile environmentwithin a turbine. Thus, there remain significant problems to overcome inefforts to improve turbine engine efficiency without necessarily seekingever more exotic and expensive materials.

The present invention is directed to overcoming one or more of theproblems set forth above.

DISCLOSURE OF THE INVENTION

A low friction bearing comprises a first element having a first surface.A second element having a second surface is rotatable about a centerlinerelative to the first element. A flow passage extends radially outwardbetween the first surface and the second surface. The first surface andthe second surface are separated by a fluid flow. The two surfaces arecomplementary and positioned in close proximity.

In one application of the present invention, a turbine comprises a firstcomponent that includes a first surface out of contact and adjacent asecond component including a second surface. The second component has aplurality of blades and is rotatable about a centerline relative to thefirst component. A flow passage extends radially outward between thefirst component and the second component. The first surface and thesecond surface are complementary and in close proximity. The firstsurface and the second surface are separated by a fluid flowing in theflow path and a source of fluid is connected to one end of the flowpath.

In another application of the present invention, each of the pluralityof blades in the turbine described above is hollow and includes acooling passage. One end of each cooling passage is fluidly connected tothe source of fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a mechanical system according tothe present invention.

FIG. 2 is a sectioned top view of the mechanical system of FIG. 1 asviewed along section lines 2—2.

FIG. 3 is a sectioned side view of the turbine of FIG. 2 as viewed alongsection lines 3—3.

FIG. 4 is a sectioned view of the turbine blade of FIG. 3 as viewedalong section lines 4—4.

FIG. 5 is a top view of one of the turning blades from FIG. 4.

FIG. 5a is a view of the front edge of the turbine blade from FIG. 5.

FIG. 5b is a view of the rear edge of the turbine blade from FIG. 5.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring now to FIG. 1 there is shown a schematic representation of amechanical system 11 according to the present invention. Mechanicalsystem 11 includes a mechanical device 20, which is preferably a turbineengine, but could be virtually any machine having rotating elements.Turbine 20 is comprised of a number of components that are mounted on atleast one of a stationary hollow shaft 21 and a rotatable shaft 22, andsupported by a frame or housing 12. In this example, turbine 20 is aradial turbine that is driven to rotate in a conventional manner bypressurized gas that is from a source of pressurized gas 15 that isdirected onto the surface of the turbine blades via a high pressuresupply line 16 in a conventional manner. Those skilled in the art willappreciate that the principles of the present invention are equallyapplicable to axial turbines and like devices. Turbine 20 includes a lowfriction bearing 10 and a cooling circuit that preferably use a commonsource of fluid 14, which is preferably a liquid such as water. Fluidsource 14 is preferably maintained at a relatively high pressure so thatfurther control over the device can be gained by controlling therespective pressures used to operate the respective low friction fluidbearing 10 and the turbine cooling circuit.

Low friction bearing 10 includes a first component 29 that is astationary member, or a stator 30. Stator 30 is mounted on hollow shaft21 and supported by frame 12. Stator 30 includes a a first interiorsurface, first surface 31 that is adjacent a second interior surface,second surface 36, of a second component 34. First component 29 andsecond component 34 preferably have circular perimeters and share acommon centerline 23. Additionally, while first component 29 and secondcomponent 34 are preferably planar surfaces, it should be appreciatedthat other complementary geometrical configurations would work equallywell. For instance, first component 29 and second component 34 could beother complementary surfaces such as convex or concave hemispheres. Inother words, the shape and dimensions of first surface 31 and secondsurface 36 should be such that they are nested together. While the twosurfaces are preferably almost identical, they need only have theability to be positioned in close proximity. However, first surface 31and second surface 36 must be shaped such that second component 34 canrotate relative to first component 29 about centerline 23.

Second component 34 is mounted on a rotating shaft 22 and supported byframe 12 via a journal bearing 13, or other conventional means, suchthat it is in close proximity to first component 29 yet preferablyprevented from contact with the same. In the illustrated embodiment, apower take off 28 could be located under journal bearing 13. While lowfriction bearing 10 could function well over a range of distancesbetween first component 29 and second component 34 if the properpressure and flow conditions can be created, these flow conditions areeasier to create when the components are in close proximity. Preferably,frame 12 and journal bearing 13 prevent the first component 29 andsecond component 34 from contact. Both second component 34 and rotatingshaft 22 are capable of rotating about centerline 23 relative to stator30 when turbine 20 is operational. In addition, while first component 29and second component 34 have each been illustrated as being machinedfrom single elements, it should be appreciated that either or both ofthese components could be machined from multiple elements that areattached to one another such that each functions as a separate singlecomponent.

Returning now to low friction bearing 10, hollow shaft 21 defines afluid passage 24 that can fluidly connect source of fluid 14 to acontrol area 33 between first surface 31 and second surface 26 to createa interaction fluid circuit. When fluid flows through fluid passage 24,a flow passage is created in control area 33 that extends radiallyoutward from centerline 23. In order to allow first component 29 andsecond component 34 to function as a low friction fluid bearing, thepresent invention exploits the Bernoulli effect to create a relativelylow pressure area within control area 33. In other words, the pressureforce on second surface 36 within control area 33 is decreased to belowan environmental pressure force acting on a second external surface 54of second component 34. The fluid bearing is controlled via ainteraction circuit valve 18 located in interaction fluid circuit 26 inorder to control both fluid pressure and flow rate in the control area33.

Bernoulli's principle is represented by the equation:

P ₁+½ρv ₁ ² =P ₂+½ρv ₂ ²  (1)

where P_(n) is static pressure of the fluid at point n and ½ρ v_(n) ² isthe dynamic pressure at point n. The Bernoulli effect is a result of theconservation of energy equating the total mechanical energy at point 1to the total mechanical energy at point 2. However, it should beappreciated that this equation is only approximate because it ignoressuch factors as friction losses, temperature variation, viscosity,density variation and others. In addition, the equation of continuitystates that for an ideal, incompressible fluid flowing in a flow path ofvarying cross-section, the mass flow rate is the same at all pointsalong the flow path. The equation of continuity can be represented bythe following equation:

ρ₁A₁v₁=ρ₂A₂v₂  (2)

where ρ is the density, A is the cross-sectional area and v is thevelocity of the fluid. For illustrative purposes, assuming an ideal,constant density fluid, equation (2) can be reduced to:

A₁v₁=A₂v₂  (3)

It should be appreciated that, assuming the distance between the platesto be constant, the velocity of the fluid drops as if flows out from thecenter. This occurs in the case of the illustrated embodiment becausethe flow area increases with the radial distance away from centerline23, which must result in a corresponding velocity drop in order tosatisfy the continuity equation.

Further, if the fluid velocity in fluid passage 24 is assumed to be verylow, or negligible, equation (1) can be reduced to:

P ₁ =P ₂+½ρv ₂ ²  (4)

Equations (3) and (4) are useful in showing that the velocity drops asthe flow moves away from the center in control area 33, and the staticpressure increases correspondingly.

Returning now to FIG. 1, low friction bearing 10 will only function asdesired when the flow conditions within control area 33 are such thatfirst component 29 and second component 34 interact. In other words,when the net pressure force acting on journal bearing 13 is an upwardforce, second component 34 is said to be interacting with firstcomponent 29. In order for the first component 29 and second component34 to be considered interacting in the sense of the present invention,the net pressure force acting on second component 34 must at leastpartially counteract its constant downward weight force. Thus, the lowfriction bearing 10 of the present invention not only acts as asubstitute for a conventional bearing, but also can be used to relievepotentially detrimental axial forces acting on the other bearing, whichin this case is journal bearing 13.

Recall that the pressure acting on second surface 36 is not constant,but increases as the flow moves away from centerline 23. Therefore, thenet force acting on second surface 36 must be determined by integratingthe pressure at each point along the flow path. For simplicity, thepressure acting upward on second external surface 54 can be assumed tobe a constant atmospheric pressure. In a practical application, thisexternal pressure would correspond to a pressure within a casingcontaining the turbine device. The external pressure force acting onsecond component 34 can then be reduced to an upward acting externalpressure force equal to the environmental pressure exposed to secondexternal surface 54 multiplied by the area of second surface 36, whichis about equal to the effective area of second external surface 54. Thedownward acting pressure force within control area 33 is equal to thepressure within control area 33 multiplied by the area of second surface36. The downward acting weight force equal to W is assumed to beconstant. Therefore, the relation of forces acting on journal bearing 13can be reduced to:

−W−ƒ ₀ ^(R)2πrd P _(e) dr+πR ² P _(e) =F _(net)  (5)

where W is the weight of second component 34, 2πrd P_(e) dr is the forceacting against second surface 36, and πR²P_(e) is the upward pressureforce acting on second external surface 54, assumed to be a constantforce for purposes of this illustration, and R corresponds to the radiusof second surface 36. Recall that the net pressure acting on secondsurface 36 of second component 34 is a function of velocity of the fluidin control area 33. Therefore, it should be appreciated that the flowconditions within low friction bearing 10 must be such that the netpressure force acting down on second surface 36 must be less that thenet atmospheric force acting upward on second external surface 54. Inother words, control area 33 must be a low pressure area relative to theenvironmental pressure acting on second external surface 54. Preferably,the net upward pressure force on second component 34 is about equal,such that rotating shaft 22 “floats” in journal bearing 13 in a way thatit no longer needs to support the weight of the components positionedabove it.

It should be appreciated that Bernoulli's equation (1) assumes anincompressible ideal, or frictionless liquid. In other words,adjustments might need to be made for friction, changes in density, andunsteady flows etc., in order to use the equations to make accuratequantitative predictions. For example, if first surface 31 and secondsurface 36 are rough surfaces, the fluid flowing through control area 33would become turbulent, and equation (1) would need to be adjustedcorrespondingly if a more accurate quantitative answer was desired.

In addition, it should be appreciated that the present invention willonly function as desired in an environment where there is at least somemeasurable pressure force acting on second external surface 54. In otherwords, first component 29 and second component 34 could not beinteracting using the present invention in a vacuum. This is truebecause the components of low friction bearing 10 will only beinteracting when the pressure force acting downward on second surface 36is less than the environmental pressure force acting upward on secondexternal surface 54. Because it would be impossible to reduce thepressure within control area 33 to below zero, second component 34 couldnot be drawn toward first component 29 in that instance. Further, forpurposes of this disclosure, the environmental pressure acting on secondexternal surface 54 is assumed to be atmospheric pressure at sea level.However, it should be appreciated that the present invention would alsowork if the pressure was much greater, such as at some point below sealevel, or at low pressures, such as at high altitudes. In eitherinstance, the velocity of the fluid and its corresponding staticpressure within control area 33 must be adjusted depending upon theexternal pressure forces acting on the turbine.

Referring now to FIGS. 2 and 3, turbine 20 is driven to rotate in anyconventional manner such as by pressurized gas from a source 15. In thisaspect of the present invention, low friction bearing 10 includes stator30, which is once again shown as being machined from a single element.Stator 30 is mounted on hollow shaft 21 and includes a first surface 31that is adjacent a second component 34. Second component 34 is mountedon rotating shaft 22 and supported by a frame such that it is in closeproximity to first component 29 yet prevented from contact with thesame. Second component 34 is comprised of a plurality of elementsincluding a pair of rotating plates 35, 50 that are separated by aplurality of turbine blades 40. Rotating plate 35 includes a secondsurface 36 that is adjacent first surface 31. While any conventionalmethod of attachment would work, rotating plates 35, 50 and each turbineblade 40 have been illustrated as being secured together by a number ofbolts 52. While second component 34 has been illustrated utilizing twobolts 52 to secure each turbine blade 40 to rotating plates 35 and 50,it should be appreciated that a different number of bolts and/or anysuitable attachment means, such as welding, could be used.

Referring again to FIGS. 1-3, the fluid cooling circuit includes acooling fluid circuit 25 that has on end connected to fluid source 14and its other end positioned within a fluid distributor 53, which iscentrally located within turbine 20. Although the cooling circuitpreferably uses the same fluid as that of the interaction fluid circuit,the fluid flow through the two different circuits can be independentlycontrolled via cooling circuit valve 17 and interaction circuit valve18, respectively. The advantage of using the same fluid in both theinteraction and cooling circuits allows the possibility of eliminatingany fluid seals between these two circuits. In the preferred embodiment,some fluid exchange can occur between the interaction fluid circuit 26and the cooling fluid circuit 25 via a clearance area 27 that existsbetween the outer diameter of the cooling fluid circuit 25 and the innerdiameter of a central bore through rotating plate 35. Those skilled inthe art will appreciate that in order to independently control the twofluid circuits, the amount of fluid flow permitted to pass between thefluid circuits via clearance area 27 should be minimized. Upon reachingfluid distributor 53, the cooling fluid flows radially outward throughcooling passages 49 that are connected to individual hollow interiors 42of turbine blades 40. Individual turbine blades 40 define fluid outlets41 on the outer radial edge of turbine 20. While the cooling fluid andthe bearing or interaction fluid have both been shown as flowing throughflow passage 24, it should be appreciated that this need not be thecase. For instance, the cooling fluid could be delivered to fluiddistributor 53 via a separate passage, and fluid distributor 53 could beblocked from fluid communication with fluid passage 24.

Referring now in addition to FIGS. 4-5b, there are shown a variety ofviews of turbine blades 40. As illustrated in FIG. 5, the interior ofturbine blade 40 is hollow, with the exception of a pair of bolt sleeves43, through which bolts 52 are secured. Turbine blade 40 includes abottom surface 46 and a top surface 47 to which bolt sleeves 43 areattached in a conventional manner, such as by welding. This constructioninsures against fluid leakage where the upper and lower surfaces ofturbine blade 40 come in contact with the inner surfaces of respectiverotating plates 35 and 50. Each turbine blade 40 includes a rear edge 44that defines an inlet 48.

A cooling passage 49 (FIG. 3) fluidly connects turbine blade 40 to fluiddistributor 53 via inlet 48. Therefore, when fluid passage 24 is fluidlyconnected to a source of pressurized fluid 14 via cooling fluid circuit25, turbine blade 40 is in fluid communication with the same via coolingpassage 49 and inlet 48 because turbine blade 40 is hollow, except forbolt sleeves 43, fluid can flow from rear edge 44 toward front edge 45and exit turbine blade 40 through a pair of fluid outlets 41. Inaddition to this cooling function, the cooling flow can torque theturbine to rotate in the same direction as the external forces to reducelosses associated with cooling. Thus, by arranging a cooling circuit asillustrated, the passage of cooling fluid through the turbine actuallyproduces a slight torque in the desired rotational direction of theturbine. Thus, a cooling circuit according to the present invention candecrease energy losses and improve efficiency in the overall operationof the turbine that might not otherwise be possible with coolingstrategies associated with prior art devices.

Each turbine blade 40 is preferably constructed by taking a piece ofsheet metal and bending it into the air foil shape as shown andproviding a central weld at the rear edge 45 as shown in FIG. 5. Next,top and bottom plates having the same air foil shape are welded orotherwise attached at their perimeter to the respective top and bottomof the sheet metal air foil shape. Next, sleeves are incorporatedbetween the end caps and a relatively short cooling passage 49 isattached to the front edge of each blade. The result being an individualturbine blade with a hollow interior that is isolated from the outsideexcept for centrally located fluid inlet 48 and a radially outwardlocated fluid outlet 41. The structure also permits attachment betweenplates 35 and 50 without concern for possible fluid leakage at theabutment between the upper and lower surfaces of the turbine blades andthose plates.

System Operation

Referring now to FIG. 3, just prior to activation of turbine 20, nofluid is flowing through either the interaction fluid circuit or thecooling fluid circuit, and second component 34 is at rest. To initiatethe interaction of components within low friction bearing 10, fluidsource 14 is placed in fluid communication with fluid passage 24 byopening interaction circuit valve 18. As fluid flows into control area33, it begins to flow radially outward over second component 34. Oncethe pressure force acting on second surface 36 drops below theenvironmental force acting on second external surface 54, secondcomponent 34 is interacting with first component 29. When the netpressure force acting on journal bearing 13 is upward, first component29 and second component 34 are interacting. The desired operatingcondition is where the net pressure force is about equal to the weightof second component 34 such that journal bearing 13 does not have tosupport the weight of second component 34. Those skilled in the art willappreciate that with appropriate flow conditions between components 29and 34, the net pressure force can actually exceed the weight of thesecond component 34 such that it is actually pulled or drawn towardfirst component 29. For this purpose, the journal bearing is preferablypositioned such that the two components are mechanically constrainedfrom coming in contact with one another.

After the requisite flow conditions have been created to allow the firstcomponent to interact with the second component, the cooling circuit canbe initiated. This is accomplished by opening cooling circuit valve 17to begin fluid flow to the interior of the turbine blades 40. Because ofthe torque produced on the turbine due to the structure of the coolingcircuit, the turbine will begin to rotate. Next, the high pressure line16 from the high pressure gas source is opened in order to drive theturbine to rotate.

The present invention creates a low friction fluid bearing by creating arelatively low pressure area between a stationary component and arotating component when a fluid is introduced between the same. Thus bycontrolling flow conditions such as distance between the components,velocity of the fluid, etc., a net positive upward pressure force actingon the rotating component can be created to allow it to interact withthe stationary member. Therefore, when the rotating component is atleast partially lifted toward the stationary component as a result ofthis interaction, the journal bearing supporting the second component isrelieved of some or all of the weight load that it would ordinarilybear. Additionally, the fluid is less resistive to relative motion, i.e.rotation, than some intervening bearing, such as a ball bearing. Inother words, by simultaneously reducing the load on the journal bearing13 and by having a very low friction bearing via the low friction fluidbearing 10, substantial friction losses in turbine 20 can be reducedrelative to its conventional bearing counterparts.

Not only does the present invention create a bearing that is exposed tolower friction than traditional bearing, it can also extend the life ofother bearing being used in the same mechanical device or system. Forinstance, in a turbine having a first component and a second componenteach supported by conventional bearings, the present invention caneliminate one bearing and reduce the load supported by the otherbearing, thereby helping to extend the life of the remaining bearing. Inthat instance, when the pressure force exerted on the components is apositive, upward force, the first and second components will beinteracting, and therefore, an amount of the weight that would otherwisebe supported by the lower bearing will be reduced.

It is believed that turbine engines having a structure with both acooling and interaction fluid circuit of the type previously describedcan produce overall engine efficiencies that could exceed 70 percent. Inany event, by utilizing the fluid interaction circuit of the presentinvention to produce a low friction fluid bearing, the overall frictionon a system can be significantly reduced and thus increase itsefficiency. By also incorporating a fluid cooling circuit into thesystem, a turbine could be operated at significantly higher temperaturesthan that possible with conventional non-cooled devices, which wouldnormally result in a substantial increase in efficiency in proportion tothe increased operating temperature. Finally, by using the same fluidsin both the fluid interaction and the fluid cooling circuits, anypotentially problematic fluid seals can be eliminated from the systemthus providing not only a more efficient turbine engine but a morerobust one as well. The present invention also makes it possible to useless exotic materials in a turbine engine without otherwise sacrificingon performance.

It should be understood that the above description is intended forillustrative purposes only, and is not intended to limit the scope ofthe present invention in any way. For instance, while the source offluid has been illustrated as being fluidly connected to the hollowshaft, it should be appreciated that it could be fluidly connected tothe low friction fluid bearing in any conventional manner that wouldallow fluid to be channeled radially outward between the first andsecond components. Further, while the present invention has beenillustrated utilizing liquid to separate the rotating component from thestationary component, it should be appreciated that either gas or acombination of liquid and gas could instead be utilized. Additionally,while the stationary component of the present invention has beenillustrated as being a single element, it should be appreciated that itcould instead be made of two or more pieces attached together tofunction as a single component. Thus, those skilled in the art willappreciate that various modifications could be made to the disclosedembodiments without departing from the intended scope of the presentinvention, which is defined in terms of the claims set forth below.

What is claimed is:
 1. A low friction bearing comprising: a firstcomponent having a first interior surface and a first external surface;a second component having a second interior surface, a second externalsurface and being rotatable about a centerline relative to said firstcomponent; a flow passage extending in all radial directions outwardaway from said centerline between said first interior surface and saidsecond interior surface; said first interior surface and said secondinterior surface being separated by a first fluid flowing in said flowpassage, and said first fluid being a liquid; said first externalsurface and said second external surface being in contact with a secondfluid; and said second component being drawn toward said first componentand at least in part by pressure forces exerted by said first fluid andsaid second fluid on said first component and said second component. 2.The low friction bearing of claim 1 wherein said first interior surfaceand said second interior surface are planar.
 3. The low friction bearingof claim 1 wherein said first interior surface has a first perimeter andsaid second interior surface has a second perimeter; and said firstperimeter and said second perimeter are circular and equal in size. 4.The low friction bearing of claim 1 further comprising a mechanicalmeans for preventing said second component from contacting said firstcomponent.
 5. The low friction bearing of claim 1 wherein a staticpressure force from said first fluid on said second interior surface isless than an outside pressure force from said second fluid on saidsecond exterior surface of said second component.
 6. A turbinecomprising: a first component including a first interior surface and afirst external surface, and being out of contact with a second componentand adjacent said second component; said second component including asecond interior surface and a second external surface; said secondcomponent having a plurality of turbine blades and being rotatable abouta centerline relative to said first component; a flow passage extendingin all radial directions outward away from said centerline between saidfirst component and said second component; said first interior surfaceand said second interior surface being separated by a first fluidflowing in said flow passage, and said first fluid being a liquid; asource of interaction fluid connected to one end of said flow passage;said first external surface and said second external surface being incontact with a second fluid; and said second component being drawingtoward said first component at least in part by pressure forces exertedby said first fluid and said second fluid on said first component andsaid second component.
 7. The turbine of claim 6 wherein each of saidplurality of turbine blades includes a cooling passage; and one end ofsaid cooling passage is fluidly connected to a source of cooling fluid.8. The turbine of claim 7 wherein said source of interaction fluid andsaid source of cooling fluid contain substantially identical liquids. 9.The turbine of claim 6 wherein said first interior surface and saidsecond interior surface are planar.
 10. The turbine of claim 6 whereineach of said plurality of turbine blades defines a hollow interiorpositioned between an inlet and an outlet, and further defines at leastone fastener bore isolated from said hollow interior.
 11. The turbine ofclaim 6 further comprising a mechanical means for preventing said secondcomponent from contacting said first component.
 12. The turbine of claim6 wherein said first interior surface and said second interior surfaceare circular and equal in size.
 13. The turbine of claim 6 wherein saidplurality of turbine blades define a portion of a cooling fluid circuitfluidly connected to said source of interaction fluid.
 14. The turbineof claim 6 wherein each of said plurality of turbine blades includes acooling passage, and one end of said cooling passage is fluidlyconnected to a source of cooling fluid; said source of interaction fluidand said source of cooling fluid are fluidly connected to a common fluidsource; and said first interior surface and said second interior surfaceare circular and planar.
 15. A method of providing an interactionbetween two components comprising: positioning a first componentincluding a first interior surface in close proximity with a secondcomponent including a second interior surface; rotating said secondcomponent relative to said first component; channeling a first fluid ina flow passage that extends in all radial directions outward betweensaid first interior surface and said second interior surface, whereinsaid first fluid is a liquid; exposing a first external surface of saidfirst component and a second external surface of said second componentto a second fluid; and drawing said second component toward said firstcomponent, at least in part by pressure forces exerted by said firstfluid and said second fluid on said first component and said secondcomponent.
 16. The method of claim 15 wherein said step of positioningsaid first component in close proximity with said second componentincludes mounting said first component on a hollow shaft and mountingsaid second component on a rotatable shaft; aligning said hollow shaftand said rotatable shaft along a common centerline of said firstcomponent and said second component; and said channeling step includes astop of fluidly connecting said hollow shaft to a source of interactionfluid.
 17. The method of claim 16 further comprising the step ofattaching a plurality of turbine blades to said second component; andsaid rotating step includes a step of applying a fluid pressure force tosaid turbine blades.
 18. The method of claim 17 wherein said rotatingstep includes applying torque to said second component via fluid forceson said turbine blades.
 19. The method of claim 18 wherein said step ofapplying torque to said second component includes channeling an amountof fluid from a source of cooling fluid through said plurality ofturbine blades.
 20. The method of claim 17 wherein said channeling stepincludes a stop of routing a portion of said first fluid to a coolingfluid circuit and routing a different portion of said first fluid to aninteraction fluid circuit.